19717668 has 60 divisors (see below), whose sum is σ = 54275760. Its totient is φ = 6224688.

The previous prime is 19717657. The next prime is 19717681. The reversal of 19717668 is 86671791.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 4555 + ... + 7757.

It is an arithmetic number, because the mean of its divisors is an integer number (904596).

Almost surely, 2^19717668 is an apocalyptic number.

19717668 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19717668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27137880).

19717668 is an abundant number, since it is smaller than the sum of its proper divisors (34558092).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19717668 is a wasteful number, since it uses less digits than its factorization.

19717668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3238 (or 3227 counting only the distinct ones).

The product of its digits is 127008, while the sum is 45.

The square root of 19717668 is about 4440.4580844773. The cubic root of 19717668 is about 270.1584255424.

The spelling of 19717668 in words is "nineteen million, seven hundred seventeen thousand, six hundred sixty-eight".